.bigbox{
    width: 400px;
    height: 500px;
    padding-bottom: 50px; 
    position: relative;
    background-color: red;
}
.box{
    width: 300px;
    height: 400px;
    margin: 0 auto;
    background-color: white;
    /* 边框圆角 */
    border-radius: 5px;
    position: absolute;
}
.top{
    width: 100%;
    height: 40px;
    background-color: lightgray;
    /* 边框的圆角 */
    border-top-left-radius: 5px;
    border-top-right-radius: 5px;
}
.top p{
    font-size: 14px;
    color: orange;
    /* 行高 */
    line-height: 40px;
    /* 居中 */
    text-align: center;
}
.login{
    margin-left: 20px;
    margin-right: 20px;
    margin-top: 50px;
}
.login .pwd{
    font-size: 18px;
    font-weight: bold;
    margin-right: 20px;
    color: red;
    
}
.login .msg{
    font-size: 18px;
    margin-right: 20px;
    color: gray;
}
input{
    outline: none;
}
.inp{
    width:260px;
    height: 30px;
    margin-top: 10px;
    text-indent: 5px;
    border: 1px solid gray;
}
.btu{
    width: 200px;
    height: 50px;
    background-color: red;
    border: none;
    font-size: 20px;
    color: white;
    font-weight: bold;
    margin-top: 40px;
    margin-left: 30px;
    border-radius: 10px;
}
.footer{
    width: 100%;
    height: 60px;
    background-color: rgb(212, 212, 214);
    margin-top: 30px;
    border-bottom-left-radius: 5px;
    border-bottom-right-radius: 5px;
    line-height: 60px;
}
.footer .a{
    margin-left: 30px;
    text-decoration: none;
    color: black;
}
.footer a:nth-of-type(3){
    margin-left: 50px;
}
.footer a:hover{
    text-decoration: underline;
}
